LAS VEGAS ­— Jaylen Brown has attracted a special spectator this week. Shareef Abdur-Rahim, a former Hawks and Kings star, is one of the Celtics rookie’s many mentors.

Since his youngest brother, Bilal, played with Brown at Wheeler High School in Marietta, Ga., Abdur-Rahim has been familiar with Brown’s uber-athletic game for quite some time. He has no doubt those tools and skills are going to lead to a significant NBA career.

“His whole life nobody has been able to stop him from getting to the rim,” said the former power forward. “Now he’ll have to adjust to that, but you know he’ll put in the work.”

That work, specifically, will include a lot of time working on his jumper, though Brown continues to get better over a short stretch of time, including 25 points and nine rebounds in the Celts’ 98-94 summer league loss to Cleveland last night.

“He doesn’t have a bad shot. The thing for him is that he’s taking those shots,” said Abdur-Rahim, who is now the NBA’s associate vice president of basketball operations. “He’s not a guy who’s going to turn a shot down. He’s not a non-shooter. People have to account for him wherever he is on the floor, including out at the 3-point line. He’s with a really good organization and coaches who are going to work with you.

“Another thing is though he’s a young kid, nobody is going to have to call him and ask him to come to the gym. He’ll already be in the gym. Nobody will have to put up extra shots. He’ll put up those extra shots. Everything is here for him to improve his shot.”

Brown has collected quite the team of advisers and mentors, including one member of NBA royalty (Isiah Thomas) and another who has played with and coached royalty in Brian Shaw.

But no one has been closer to home for the Celtics rookie than Abdur-Rahim.

“I had two young brothers who went to high school with him. One of them (Bilal) is the same age, same grade,” Abdur-Rahim said. “They played together. They’re all around the playground and stay connected.”

Brown also went to Abdur-Rahim’s other alma mater, the University of California. Contrary to common perception, he insists he had nothing to do with Brown’s college choice.

“I didn’t, though people think that,” Abdur-Rahim said. “I told him about some of the success and how it worked out for me, but I never talked to him about going to Cal. In the end, Cal was an option, but as far as introducing it as an option and advocating for it, no.”

Final shot in Vegas

The Celtics, now 1-3 in Las Vegas, will play one last game tomorrow (6 p.m. eastern) against Portland. But R.J. Hunter’s summer league may be over. The guard fell on the wrist on his shooting hand again yesterday, and didn’t return after a 3-point, 17-minute stint.

“We’ll see. We don’t play again until Friday, so we’ll see what it looks like,” Hunter said of whether he plays in the last game. “Just keep icing it. They’ll take a look at it tomorrow. I haven’t heard about any more tests. I got an X-ray in Utah and it was fine. It just needs rest. I just keep falling on it.”

Approve the minutes

With the Celtics facing the potential of three playoff games over the next three days, Jamie Young has to start monitoring minutes, and especially those of Terry Rozier, who played 31 minutes in Tuesday’s win over Dallas, and 26 minutes in his 24-point performance last night.

“I already told Terry he’s not going to play as many minutes,” said the Celtics assistant, who is coaching the summer team here. “He’s going to play, and he’s going to compete obviously. He’s not real happy about it, but we are going to try and scale him back a little bit. He’s not going to play as many minutes as he played last night. I’m going to try and not play him that much, obviously. (Nobody is) sitting. Terry’s the only one we’re going to try and back off of a little bit.”

Rozier’s cutback on playing time has increased the opportunities for DemetriusJackson, the second-round pick out of Notre Dame who was not expected to slide out of the first round.

Time to shine

Celtics president of basketball operations Danny Ainge recently said that now is the time for James Young to show progress in his game. Heading into last night’s game against Cleveland, Young had shot 14-for-38 (34 percent) overall and 9-for-16 (46 percent) on 3-pointers during his first five games.

“I’m sure it’s on him, third year, he probably wants to prove himself,” Jamie Young said. “There’s a little pressure. It’s not as if he has to go out and score 25 points. He just has to make shots — make shots and defend. Those are the things he has to show he can do, and he’s shown it.”

But in something of a foreboding note for Young, he missed the only shot he attempted and played only seven minutes yesterday, including none in the fourth quarter.

Mark Murphy covered his first NBA season for the Boston Herald in 1989-90, Jimmy Rodgers' last as Celtics coach and a point when injuries were starting to overtake the careers of Larry Bird and Kevin McHale. He was one of the first NBA writers to cover professional basketball in the Olympics with the 1992 Dream Team in Barcelona, and took a detour out to western Massachusetts to chronicle the rise of John Calipari and UMass basketball. He returned to the Celtics beat in 2001, and was on hand for the dawn of a second Big Three era - this time with Paul Pierce, Kevin Garnett, Ray Allen and the Celtics' 17th NBA title in 2008.

Mark Murphy covered his first NBA season for the Boston Herald in 1989-90, Jimmy Rodgers' last as Celtics coach and a point when injuries were starting to overtake the careers of Larry Bird and Kevin McHale. He was one of the first NBA writers to cover professional basketball in the Olympics with the 1992 Dream Team in Barcelona, and took a detour out to western Massachusetts to chronicle the rise of John Calipari and UMass basketball. He returned to the Celtics beat in 2001, and was on hand for the dawn of a second Big Three era - this time with Paul Pierce, Kevin Garnett, Ray Allen and the Celtics' 17th NBA title in 2008.